spll_3ph_srf.h

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//#############################################################################
//
//  FILE:   splll_3ph_srf.h
//
//  TITLE:  Software Phase Lock Loop for Three Phase Grid Tied Systems
//
//#############################################################################
 
#ifndef SPLL_3PH_SRF_H
#define SPLL_3PH_SRF_H
 
#ifdef __cplusplus
extern "C" {
#endif
 
//
// Included Files
//
#include <stdint.h>
#include <math.h>
 
//#############################################################################
//
// Macro Definitions
//
//#############################################################################
#ifndef IEEE754_TYPES
#define IEEE754_TYPES
typedef float         float32_t;
typedef double        float64_t;
 
#endif // IEEE754_TYPES
 
//
// Typedefs
//
 
typedef struct{
    float32_t b1;
    float32_t b0;
} SPLL_3PH_SRF_LPF_COEFF;
 
typedef struct{
    float32_t v_q[2];     
    float32_t ylf[2];     
    float32_t fo;         
    float32_t fn;         
    float32_t theta[2];   
    float32_t delta_t;    
    SPLL_3PH_SRF_LPF_COEFF lpf_coeff;  
} SPLL_3PH_SRF;
 
static inline void SPLL_3PH_SRF_init(float32_t grid_freq, float32_t delta_t,
                                     SPLL_3PH_SRF *spll_obj)
{
    spll_obj->v_q[0] = (float32_t)(0.0);
    spll_obj->v_q[1] = (float32_t)(0.0);
 
    spll_obj->ylf[0] = (float32_t)(0.0);
    spll_obj->ylf[1] = (float32_t)(0.0);
 
    spll_obj->fo = (float32_t)(0.0);
    spll_obj->fn = (float32_t)(grid_freq);
 
    spll_obj->theta[0] = (float32_t)(0.0);
    spll_obj->theta[1] = (float32_t)(0.0);
 
    spll_obj->delta_t = (float32_t)delta_t;
}
 
static inline void SPLL_3PH_SRF_reset(SPLL_3PH_SRF *spll_obj)
{
    spll_obj->v_q[0] = (float32_t)(0.0);
    spll_obj->v_q[1] = (float32_t)(0.0);
 
    spll_obj->ylf[0] = (float32_t)(0.0);
    spll_obj->ylf[1] = (float32_t)(0.0);
 
    spll_obj->fo = (float32_t)(0.0);
 
    spll_obj->theta[0] = (float32_t)(0.0);
    spll_obj->theta[1] = (float32_t)(0.0);
 
}
 
static inline void SPLL_3PH_SRF_run(float32_t v_q, SPLL_3PH_SRF *spll_obj)
{
    //
    // Update the spll_obj->v_q[0] with the grid value
    //
    spll_obj->v_q[0] = v_q;
 
    //
    // Loop Filter
    //
    spll_obj->ylf[0] =  spll_obj->ylf[1]
                     + (spll_obj->lpf_coeff.b0 * spll_obj->v_q[0])
                     + (spll_obj->lpf_coeff.b1 * spll_obj->v_q[1]);
    spll_obj->ylf[1] = spll_obj->ylf[0];
    spll_obj->v_q[1] = spll_obj->v_q[0];
 
    spll_obj->ylf[0] = (spll_obj->ylf[0] > (float32_t)(200.0)) ?
                                (float32_t)(200.0) : spll_obj->ylf[0];
 
    //
    // VCO
    //
    spll_obj->fo = spll_obj->fn + spll_obj->ylf[0];
 
    spll_obj->theta[0] = spll_obj->theta[1] +
                         ((spll_obj->fo * spll_obj->delta_t) *
                          (float32_t)(2.0 * 3.1415926));
    if(spll_obj->theta[0] > (float32_t)(2.0 * 3.1415926))
    {
        spll_obj->theta[0] = spll_obj->theta[0] - (float32_t)(2.0 * 3.1415926);
    }
 
    spll_obj->theta[1] = spll_obj->theta[0];
}
 
// Close the Doxygen group.
#ifdef __cplusplus
}
#endif // extern "C"
 
#endif // end of  _SPLL_3PH_SRF_H_ definition
 
//
// End of File
//